Zalli · Proceedings of the National Academy of Sciences of the United States of America 2014 · Cross-sectional laboratory stress study · n=333

Shorter telomeres with high telomerase activity are associated with raised allostatic load and impoverished psychosocial resources.

Cited 179 times in the scientific literature.

Level 4 - case-series / case-control

Cross-sectional laboratory observational study evaluating physiological stress reactivity and psychosocial variables across cellular profiles.

PubMed 24616496 · doi:10.1073/pnas.1322145111 · record verified 2026-08-30

What was done

Researchers evaluated 333 healthy men and women aged 54–76 years to examine whether leukocyte profiles characterized by shorter telomeres combined with high telomerase activity reflect elevated allostatic load and diminished psychosocial resources. Participants completed standardized laboratory mental stress tasks during which cardiovascular (blood pressure, heart rate, heart rate variability), neuroendocrine (cortisol), and inflammatory markers (monocyte chemoattractant protein-1) were assessed before and after stress. Associations with psychosocial measures (social support, optimism, hostility, early life adversity) were evaluated after controlling for age, socioeconomic status, and body mass index.

What was found

The abstract reports directional findings without numerical values, effect sizes, or p-values. Mental stress tasks increased blood pressure, heart rate, cortisol, and inflammatory mediators while decreasing heart rate variability across the cohort. In men, shorter telomeres combined with high telomerase activity were associated with blunted post-stress recovery in systolic blood pressure, heart rate variability, and monocyte chemoattractant protein-1, alongside reduced responsivity in diastolic blood pressure, heart rate, and cortisol compared to men with longer telomeres or shorter telomeres with low telomerase activity. This profile in men was also associated with reduced social support, lower optimism, higher hostility, and greater early life adversity. No significant associations were observed among older women.

Why it matters

This study shows that considering both telomere length and telomerase activity identifies a cellular stress profile associated with impaired systemic stress regulation and poorer psychosocial resources in older men.

Limits

The abstract provides no exact numerical data, confidence intervals, or effect sizes. The cross-sectional design cannot establish causality between cellular markers, physiological stress responses, and psychosocial resources. Findings were observed only in older men, limiting generalizability to women and younger populations.

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